The present invention relates to a contact lens disinfector unit having an improved temperature indicator.
Disinfector units frequently include a lens case which makes broad surface contact with a block that is heated by an electric current. After heating the lenses at a disinfecting temperature for a sufficient time, the application of current to the heating block is terminated and the lens case and contact lenses are allowed to cool and then removed for use.
Disinfector units of the foregoing type have generally controlled the application of electric current to the heating block with a thermocoupled switch. The thermocouple, after detecting a predetermined temperature of the heating block, breaks the switch contact for terminating the application of the electric current. Wired in series with the switch may be a light bulb. The light bulb lights up when the switch is closed and the electric current is being applied to the heating block and is turned off when the thermocouple opens the switch to terminate the application of the electric current to the heating block. Because of this arrangement, the user may not know when the contact lens case has cooled sufficiently to be safely removed. The user may therefore either attempt to remove the lens case too soon resulting in possible injury, or wait an exceedingly long time after the light bulb turns off to be assured that the lens case may be safely removed. As a result, such disinfectors are inconvenient to use and may result in injury to the user.
It is therefore an object of the present invention to provide a new and improved contact lens disinfector unit which includes a temperature indicator for indicating if the contact lens case is hot and unsafe for removal or if the lens case has cooled sufficiently for safe removal.
The present invention therefore provides a contact lens disinfector unit for sterilizing contact lenses contained within a contact lens case. The contact lens disinfector unit includes a housing, heating means arranged to heat the contact lens case and the contact lenses therein to a disinfecting temperature and for terminating the application of heat thereafter to allow the contact lenses to cool, and temperature indicating means for indicating first and second temperatures of the heating means. The temperature indicator may include a viewing window formed in the housing, prismatic lens means within the housing and behind the viewing window, first and second temperature indicia behind the prismatic lens means, wherein the prismatic lens means is arranged for movement such that the first temperature indicia is viewable through the viewing window when the prismatic lens means is at a first angular position relative to the viewing window, and the second temperature indicia is viewable through the viewing window when the prismatic lens means is at a second angular position relative to the viewing window; and actuating means responsive to the temperature of the heating means for moving the prismatic lens means between the first and second angular positions relative to the viewing window.